Temporal trends in ultrasound utilisation in the radiology department of a tertiary hospital

Background: Little is known about the combined impact of increasing ultrasound usage by clinical disciplines outside radiology and technical advances in other specialised radiological modalities on the role of ultrasound in tertiary-level radiology departments.Objectives: The aim of this study was to evaluate temporal trends in ultrasound utilisation in a tertiary-level radiology department.Method: An institutional review board-approved retrospective descriptive study in the radiology department of Tygerberg Hospital (TBH). The nature and number of ultrasound performed in 2013 and 2019 were retrieved from the TBH radiology information system (RIS). These were compared, expressed as a proportion of the overall annual radiology workload and stratified by location (ultrasound suite, interventional suite, mammography suite). Ultrasound suite examinations were analysed by body part and age (0–13 years; 13 years) and interventional suite workload by procedure.Results: The overall radiology workload decreased by 8%, reflecting the interplay between decreased plain radiography (–19%) and general fluoroscopy (–0.3%) and increased computed tomography (27%), magnetic resonance (23%) and fluoroscopically guided procedures (22%).There was a 12% increase in ultrasound utilisation. Ultrasound remained the second most common specialised imaging investigation throughout, after computed tomography. Ultrasound suite services were stable (–1%) representing a balance between decreased abdominal (–22%) and arterial (–16%) scans, and increased musculoskeletal (67%), small part (65%) and neonatal brain scans (41%). There were substantial increases in interventional (90%) and mammography suite (199%) services.Conclusion: Ultrasound remains a key modality in the tertiary-level radiology department, with an evolving pattern of clinical applications.

Measurement of thyroglobulin, calcitonin, and PTH in FNA washout fluids

Different imaging tools, circulating endocrine markers, and fine-needle aspiration (FNA) cytology are of great importance in the diagnosis and follow-up of different thyroid and parathyroid diseases. Sometimes, however, they are conflicting or inconclusive: interestingly, measuring endocrine markers (i.e. thyroglobulin, calcitonin, parathyroid hormone) in fluids from FNA proved to be a very useful complementary diagnostic tool in such cases. The determination of endocrine markers in fluids other than serum/plasma has been developed in the last years. Although studies have reported overall satisfactory results, a good standardization of procedures has not yet been reached, and further efforts should be made in order to better define pre-analytical, analytical, and post-analytical aspects. Here we reviewed critically the literature on the measurement of FNA endocrine markers, focusing on laboratory issues, such as preparation of the sample, choice of solution, and technical features of determination of these markers. Indeed, information for use of FNA-Tg, FNA-CT, and FNA-PTH in clinical practice was also provided.

Preoperative Localization of Enlarged Parathyroid Glands with Ultrasonically Guided Fine Needle Aspiration for Parathyroid Hormone Assay

For preoperative localization of enlarged parathyroid glands, several imaging techniques have been used. In this study we demonstrate the feasibility of using ultrasonography with fine needle aspiration for parathyroid hormone assay as a preoperative localization procedure in 21 patients with primary hyperparathyroidism. A single adenoma was found in 18 patients while 3 patients had multiglandular disease. Ultrasonically guided fine needle biopsy was possible in 11 cases. In 8 of these aspirates, a high parathyroid hormone content was found. In all 8 cases the localization was confirmed at surgery. We conclude that the efficiency to preoperatively localize enlarged parathyroid glands is enhanced by fine needle aspiration.

Fine needle aspiration and intraparathyroid intact parathyroid hormone measurement for reoperative parathyroid surgery

Some authors have praised the value of fine needle aspiration (FNA) with measurement of intraparathyroid intact parathyroid hormone (iPTH) for localization of the hypersecreting gland(s) in recurrent or persistent primary hyperparathyroidism (HPT). The aim of the present study was to determinate whether FNA for iPTH assay is an effective procedure to distinguish between normal and hypersecreting parathyroid glands. We performed a prospective study of 170 patients who underwent cervicotomy. They were divided into three groups: group A, 50 patients with thyroid diseases; group B, 100 patients with primary HPT; group C, 20 patients with secondary HPT. We performed intraoperative FNA for iPTH measurement from the thyroid, and from the normal and enlarged parathyroid glands, and we compared the different intraglandular iPTH assays. In group A, the intraparathyroid iPTH level was < 1000 pg/ml in 68% of the patients. In group B, in the pathological parathyroid gland iPTH was > 1000 in 88%; conversely, in the normal adjacent parathyroid glands it was < 1000 in 79%. In group C, intraparathyroid iPTH of enlarged glands was > 1000 in 80%. Intrathyroid iPTH was < 100 pg/ml in 96% for the three groups. We conclude that FNA for intraglandular iPTH measurement is an effective tool for distinguishing between normal and pathological parathyroid glands in the setting of primary HPT (p < 0.05), and between thyroid and parathyroid glands in groups A and B. But the procedure should be carried out in conjunction with the sestamibi scan and ultrasonography before surgical reintervention.

Parathyroid adenomas: pre-operative localization with ultrasound combined with fine-needle biopsy

Sixteen patients with biochemically proven primary hyperparathyroidism (PHPT) underwent ultrasonography (US), fine-needle aspiration (FNA) for cytologic sampling (n = 9), or intact parathormone assay (n = 3) before operation (n = 15) in order to determine the accuracy of the methods. Pre-operative US was found sensitive (100 per cent), but two thyroid lesions were initially diagnosed as parathyroid tumours by US (i.e. false positives). Parathyroid cells were detected in six cytologic specimens, one sample was insufficient and another inconclusive, while one was diagnosed as thyroid tissue. Parathormone assay revealed a high hormone content in all three patients who underwent the procedure. We conclude that US is sufficiently sensitive to detect enlarged parathyroid tumours. Specificity can be improved by US-guided FNA for cytology or parathormone assay prior to neck exploration.

Ultrasonically guided chemical parathyroidectomy in patients with primary hyperparathyroidism: a follow-up study

OBJECTIVE

We evaluated the long-term results in two different groups of patients with primary hyperparathyroidism treated with ultrasonically guided percutaneous ethanol (96%) injection into parathyroid tumours.

DESIGN

A prospective long-term follow-up (more than 6 months). Ethanol (96%) was injected under ultrasonic guidance into biopsy verified solitary parathyroid tumours. Basic treatment included a maximum of three treatments with an interval of about 1 month (group 1) or 1 week (group 2). Dose of ethanol was half the volume of the parathyroid tumour.

PATIENTS

Two different groups of patients with only one ultrasonically detected and biopsy verified parathyroid tumour were treated. Group 1 (n = 18) were treated regardless of the severity of the hyperparathyroid disease. Group 2 (n = 14) were selected for treatment either due to severe hypercalcaemic symptoms (n = 3), a high surgical risk (n = 5), or refusal of surgery (n = 6).

MEASUREMENTS

The volume of the parathyroid tumours was measured as half the product of maximum length, width, and depth. Blood tests included measurements of ionized calcium, total calcium and PTH.

RESULTS

In group 1, 12 of 18 patients (66%) could be followed more than 6 months. Follow-up ranged from 12 to 58 months (median 45 months). A significant decrease (P < 0.001) in serum concentrations of ionized calcium and total calcium was observed. Eight patients (44%) later underwent surgical parathyroidectomy. Injection therapy was regarded as successful in 10 of 18 patients (56%). In group 2, 11 of 14 patients (79%) were followed more than 6 months. Follow-up ranged from 18 to 50 months (median 39 months). A significant decrease (P < 0.001) in serum concentrations of ionized calcium, total calcium and intact PTH (1-84) was observed. Treatment was successful in 11 of 14 patients (79%). Two patients required parathyroid surgery. Re-examination with ultrasound showed a significant reduction in the volume of the treated parathyroid tumours. Fibrosis surrounding the parathyroid tumours was detected in eight of 10 patients who subsequently had operations. One patient from each group had a complication of a unilateral permanent vocal cord paralysis following injection therapy.

CONCLUSION

Partial or complete long-term remission of primary hyperparathyroidism can be achieved using ultrasound-guided chemical parathyroidectomy. However, the intervals between treatments should be short and the treatment should be reserved only for patients not fit for surgery.

Pre-operative localization and interventional treatment of parathyroid tumors: when and how?

A variety of diagnostic tests are currently used for parathyroid localization. In patients who have not had previous surgery, none of these are as sensitive or specific for the localization of abnormal parathyroid glands as an experienced surgeon. In these patients, no pre-operative localization procedures are normally needed. Patients who have had previous thyroid or parathyroid surgery require pre-operative localization. Noninvasive imaging procedures (ultrasound, scintigraphy, computed tomography, magnetic resonance imaging) should be performed until an abnormal gland is identified in the same location on at least 2 examinations. The order in which these studies are performed is not important. In the 50% to 70% of patients in whom noninvasive studies are inconclusive, suspicious lesions may be aspirated or biopsied with imaging guidance. If this cannot be done or is nondiagnostic, angiography and, if necessary, parathyroid venous sampling should be done. Intra-operative ultrasound examination of the neck is helpful during re-operations. In selected patients, parathyroid tumors may be ablated by injection of contrast material through an angiographic catheter into the artery supplying the gland, or by percutaneous injection of alcohol into the gland itself. Angiographic ablation is best used for mediastinal glands supplied by the internal thoracic artery or by a descending branch of the inferior thyroid artery. Percutaneous alcohol injection may injure the recurrent laryngeal nerve permanently and should be limited to the rare patient with a neck lesion who has a prohibitive surgical risk. Neither technique is as effective as surgery.

Percutaneous aspiration for hormone levels in the diagnosis of functioning endocrine tumors

Percutaneous aspiration to measure hormone levels in suspected functioning endocrine adenomas has been performed in 23 suspected cases of parathyroid adenomas, 7 cases of ACTH-producing thoracic carcinoid tumors, and 1 case of gastrinoma. When tumors secrete hormone or peptide markers, the biochemical assay can replace cytology to identify the lesion with greater specificity and at less expense.

Parathyroid identification by ultrasonically guided aspiration cytology. Is correct cytological identification possible?

Reliable parathyroid identification is necessary before percutaneous inactivation of parathyroid tumours is carried out. Aspiration cytology is one of the methods used for this purpose. Some, but not all, investigators have found it difficult or impossible to make a cytological distinction between thyroid and parathyroid cells. In a blind morphological study of 16 parathyroid and 16 thyroid aspirations the specificity of a cytological diagnosis of parathyroid cells was 100%. The sensitivity of the same diagnosis was 9/16 = 56% if only certain diagnosis of parathyroid cells was considered, but 14/16 = 88% if also diagnoses of "probably parathyroid cells" were considered.